Lines of Defense
by barrel7
Summary: What would happen if Eggman was incredibly fast and Sonic was the genius? An AU story.
1. A Visitor

Just so there is no confusion, this is an AU story where the hero's abilities are switched with the villain's. If Sonic is OOC in the first chapter it is because of that. Enjoy.

Disclaimer: I do not own the Sonic the Hedgehog characters

Lines of Defense

Chapter 1: A Visitor

_Dripping water? How annoying. I must have forgotten to turn off the facet. I should go fix it but I don't want to get up. Even if my bed is cold…wait?_

Tails wakes with a start as he remembers where he is, then scrambles in drowsy panic as the assortment of glassware on the work table starts to shake and fall. After righting a teetering burette and snatching a test tube from thin air, Tails slumps back in his chair with a sigh. His head is pounding now, as if in protest to its renewed activity. Setting the test tube safely in its rack he surveys the wreckage. A few upended beakers but thankfully there are no chemical spills. It really is a wonder considering how cluttered the table is. It seems like every square inch is taken up by a Bunsen burner, a scale, or a manila folder stuffed with papers. Still, it matches the rest of the room which is by no means organized. Machinery and robotic parts are strewn across the floor and large processing units take up a majority of the space.

_I really need to do something about that, _Tails decides, but without much conviction. Stretching he tries to remember what he was doing before his impromptu nap. It had been something to do with the new mineral. Was it another experiment? That was it. He had been waiting for the refined portion to dry before he nodded off.

Tails rolls his chair over to the drying oven, a device that looks something like a safe but without a lock. Opening it, he uses a pair of tongs to lift out a little clay bowl from within. The contents, a fine white powder, are dry he notes with satisfaction. Carefully he scrapes the powder onto a little metal plate.

"Now all I need is a light," he mumbles to himself as he picks out a sparker from the mess. Holding the apparatus above the powder he strikes the flint. Nothing happens. He tries again but with similar results. Looking closer at the sparker he sees that the flint is nearly gone. Sighing he starts searching through drawers until he finds a replacement underneath a positively ancient peanut butter sandwich. Putting the device back in position he is about to light it when the door opens. In walks a blue hedgehog, appearing deep in thought. He is about to say something when-

"Tails! What are you doing!" he suddenly yells.

Tails looks up in surprise at the outburst and is even more confused when the newcomer hurriedly snatches the sparker from his fingers.

"Are you trying to blow us all sky high!"

"But you said-

"Add heat _after_ adding the distilled liquid!"

Tails eyes widen in realization and he wonders at just how close he came to a fiery death.

"Did you sleep at all last night?"

"What?" The sudden question jolts Tails out of his reverie.

"You've got dark circles under your eyes. At this rate you'll look more like a raccoon than a fox."

"Well-I-um stayed up all night working."

"Again?"

"Again."

Sonic rolls his eyes and motions for Tails to add the forgotten liquid.

"I hope you see the hazard this time."

"Yeah." Tails replies as he pours the last drop onto the powder.

"Good, because it's not just your health I'm worried about. The lab is no place for distraction." The last is said with a little flourish as Sonic brings the sparker just above the moistened mineral.

"As scientists we must live with precision."

With a practiced flick he lights the concoction. The two observers wait anxiously to see what happens. It takes a minute but the mineral starts to coalesce into a deep amber crystalline form. The reaction sticks, and Tails is about to proclaim their success when it breaks down. With a dismissive gurgle the crystal collapses into a soggy gray mush. Tails looks crestfallen and Sonic sighs.

"And at times we must live with disappointment."

"Want me to get another sample?"

"No. I think we'll leave this project alone for the time being. For now, I'll see what I can do on the Hyperion model."

"I'll help too," the loyal kit says, but Sonic can tell from his voice that he barely has enough energy to keep his eyes from drooping.

"No. You are going to rest."

"But you need my help to align the circuitry."

"Actually, I was going to work on the armor today. There's an alloy I want to try that is lighter than what we've used before. The structure however will have to be arranged for the lack of durability. Maybe a different core component could fix that. Then there's a few movement joints I need to account for and…" he trails off as he sees that Tails has dozed off and curled up in his chair. Sonic just shakes his head. He was glad to have Tails as his assistant and even more so as his friend but the fox could be overzealous at times.

_Now how am I going to get him to his own bed,_ he thought knowing full well the consequences of sleeping in one of those cramped lab chairs.

A blaring alarm makes such thoughts unnecessary as the kit is jolted awake for the second time this day. Unfortunately, on this occasion the results are more destructive as a flailing kick sends a beaker flying. It sails through the air and narrowly misses Sonic's head before shattering impressively against the far wall.

"Oh h-,"before the disgruntled fox can get any farther Sonic grabs a hold of him and drags him out the door.

"While I'm sure you were about to utter a very deep and profound statement," the hedgehog chuckles as they both start running, "It appears we have an uninvited guest."

"Is it him?" Tails asks as they reach the end of the hall and step into an elevator.

"Boldly attacking a fortified city with some of the best defensive technology on the planet," the hedgehog's look darkens dangerously, "Who else could it be."


	2. First Line

Thanks to those that reviewed. This chapter is the start of the action.

Disclaimer: I do not own the Sonic characters.

Chapter 2: First Line

Sonic and Tails enter a round room with the majority of the wall space taken up by monitors and the rest denoted to processing towers and interface panels. The control room is Sonic's surveillance hub and where he deals with oncoming threats. At the moment the main screen is picturing a dust cloud that is rapidly evolving into the figure of a man. It took a second before that figure had widened considerably to reveal an overweight middle aged man in a red coat and black boots. In another second, his dome of a head, dark glasses, and wild mustache were visible. He is running at an incredible speed but somehow manages to come to a dead stop in front of the camera.

"Ivo Robotnik, otherwise known as Eggman; he's just as fast as always," Sonic says with a smile, though it doesn't quite reach his eyes.

Robotnik waves at the camera and looks as though he's speaking, but no noise reaches the control room.

"Should I turn on the audio receptor?" Tails asks.

"Do we have to? I think I like it better this way." Sonic chuckles to himself, enjoying the image of his enemy miming on the screen.

"What if he's saying something important?"

"Robotnik? Somehow I doubt that, but go ahead," Sonic concedes. Tails hits a few keys and sound starts coming from the monitor.

"-before sending this world into ruin and despair," Eggman finishes.

"See? We're mid-evil rant now. We could have just skipped the rest."

"Shh. Maybe he'll give away what he's up to."

"If it's anything more than run and smash, I'll be surprised."

"But that's enough about the future," Eggman continues, unaware of his near lack of audience, "I suppose you think you're safe in that hulking pile of scrap you call a city. Well since I was bored today, I decided to come and show you just how wrong you are. If you think a wall and a few crawling hunks of metal will stop me," he raises a gloved hand, showing off four short blades attached to it's back, "You're in for a surprise."

He lunges forward and the camera suddenly goes black. Sonic casually types in a command and the screen changes to an overhead view where Eggman is seen heading toward the city's outer wall.

"A few crawling hunks of metal?" Sonic laughs, "If he's attacking with that sort of attitude, he's the one in for a surprise."

"He'll be here in about a minute," Tails says, looking at a scanner with a fast moving red dot.

"More likely less. Have you sent out the feeler unit?"

"Already deployed," Tails replies.

"Good. Let's see if old Ivo is still up to speed." He hits another few keys and the camera changes again. This time a view of the city's outer wall comes up showing an array of tall cylindrical robots with tank like treads and two sets of guns mounted to their sides. They move into a protective ring around the perimeter of the city. Looking at different monitors, Sonic checks to see that every area of the wall is covered by a line of metallic guards.

_No easy gaps to slip through. If Robotnik wants to break into my city he'll have to fight his way in, _Sonic thought.

Approaching the defenses with a cocky grin is the mustachioed speedster himself. The robots let lose a mixture of gunfire and missiles that Robotnik easily evades. In fact, he doesn't even seem fazed, smirking through the entire assault. As a cluster of missiles explode just ahead of him, he jumps. The portly assailant rolls into a ball form in midair and slams into one of the guards with the full force gravity. He doesn't stop there. Instead he bounces away from the resulting explosion and proceeds to destroy another robot and another and another. He annihilates them in ricochet style, leaving a trail of smoke and shrapnel behind him.

"Ugh. How does he do it?" Tails asks in disgust. They weren't complex models, but these robots still took time to build. It's hard to watch hours of work being casually decimated.

"The blades on his gloves and some on the soles of his shoes are the cause," Sonic explained, "Sharp surfaces coupled with high speeds makes for a pretty effective buzz saw… it amazes me."

"I know. He mows through them like they're paper."

"Hmm? No, I meant how the robots only ever seem to explode."

"…heh?" A very confused fox utters.

"That body weight at those velocities. They should disintegrate! I mean think of the density!"

Tails just stares at him.

"What?"

"Nothing."

They return their attention to the screen to see Eggman losing his ball form and coming to a stand still. The guard robots quickly move to surround him, all guns trained on the attacker.

"We might actually have him this time," Tails cries hopefully.

"That would be disappointing."

The guards let loose and Eggman…disappears. For a moment there is complete silence on both sides of the camera. Then, half the monitors in the control room turn red as explosions erupt across the entire defensive ring. Only piles of fiery wreckage is left where before there had been lines of heavily armed robots. One last blast sounds as Eggman reappears in the exact same spot where he had been trapped. The guards that had surrounded him are nothing more than smoking rubble. Eggman yawns.

"Pfft. Showoff."

Tails groans, "All that work wasted."

"No worries. It was expected," Sonic grins, "I've already set up the secondary unit."

On screen, Eggman is running full force at the defensive wall as if he is going to ram it. Just before he reaches it, however, he jumps. The leap takes him up half the distance of the wall. He then connects with the surface and starts running again, only this time at a ninety degree angle. With speed defying gravity, he makes it over the rim and lands on top without incident.

That is, until a hidden springboard sends him flying into the sky.


	3. The Odd Army

I had a bit of writer's block with this one, but I think it turned out well. This chapter introduces Sonic's version of the badnik horde.

Disclaimer: I do not own the Sonic characters.

Chapter 3: The Odd Army

Eggman is fully disoriented as he flips through the air. It is only when he reaches the height of his flight that he resumes control. He quickly realizes as he starts to fall that the distance to the ground is too great. He tucks into his ball form and uses gravity to start spinning, hoping to lessen the force of the impact.

"Perfect," Sonic says from the control room. He types in a command and a screen beside the main monitor shows several boxes with the word ONLINE printed on them.

On a factory near the city's edge three robots blink to life and launch from their perch on a smoke stack. They open their wings to fly and use thrusters to rocket into the sky. In the air they resemble "V's" with the pointed ends aimed right at a falling sphere. The leader of the trio rushes forward and slams into Eggman kamikaze style. The robot explodes on impact, but the blast manages to throw off Eggman's trajectory. His now cannonball like descent sends him into the strong iron doors of a nearby production plant. With a sound like a gunshot he punches through. The metal at his entry point is mangled and the doors rock on their support bars.

"Ow," Tails winces at the impact.

"Poor doors. What did they ever do to him?" Sonic comments sarcastically.

Eggman jumps back into view through the hole he just made. He appears unhurt but a moment of dizziness makes him stumble. He is barely able to straighten again when he finds himself entangled in a thick sticky substance. Two threads are plastered to his arms and he looks behind him to see they are connected to two spider robots camouflaged into the walls of the plant. Eggman smirks and starts whirling around in a circle, becoming what could only be described as a mini tornado. The spiders, attached to the intruder by the threads, are pulled from the wall and start swinging wildly around the little maelstrom. If robots could feel nausea, the spider-bots would have. Finally the thread snaps and the pitiful attackers are flung far into the distance.

Eggman, meanwhile, is trying to stop but isn't having much luck. This is due mostly to a subterranean robot that decides just then to reveal itself. As it surfaces it shows a blocky body with a turn-table like discus on its back that is spinning with Eggman's rotation and keeping the intruder in motion. For a moment it appears as if Eggman is caught in his own attack, but then the rotund assailant starts to speed up. The increase in speed gives him some control over his footing, enough that he is able to jump and break out of the confines of momentum. He lands back on the discus and starts running in the opposite direction to its spin. Gears grind in the clunky body as the discus goes faster than the mechanisms can keep up with. Sparks fly from the robot's joints until it finally collapses.

Eggman casually hops off the wreckage, puts his hands on his hips, and starts laughing his trademark "Ho, hohoho" chortle that makes him sound like a demented Santa Clause. The premature gloating doesn't last long as a wave of small pointy projectiles come at him from nowhere. Quick reflexes and a couple dodges get him through a space in the onslaught. He looks around trying to find his new attacker when he spots something blinking on a nearby wall. The tiny red light is joined by others as the entire wall is lit up. The same thing happens to the wall across from it and even on a few of the street lights. Eggman's position is encased in blinking dots. The tiny apparitions are hard to identify but Eggman finally recognizes them as… starfish? Five pronged golden star robots cling to the surfaces around him. And blinking. In the half-second it takes for Eggman to think about running out of range, they fire the second volley.

What happens next sends Tails and Sonic into fits of laughter. Eggman does a pseudo split, a fire roll, a lunge, a somersault, a limbo, a duck, a slide, some back pedaling, and a near trip. He is hopping around on one foot when the starfish stop their assault, ending what had seemed to be a badly choreographed jig.

Eggman is back on two feet and feels his mustache where a dart had clipped a few hairs. He looks around and sees that all the starfish are now harmless, dull pentagons. Eggman feels a triumphant smirk coming on, but as soon as his lips twitch two spears of avian metal impact the ground. The two remaining V-shaped birds dive bomb the intruder with one landing just ahead of him and one landing just behind. Eggman, sandwiched in the middle, is stiff as a post with both arms straight in the air, trying to be as small as possible. Both birds are only a couple centimeters away from his prodigious girth. The old man is sweating now.

"Darn it," Sonic sighs, "Well, that's it for the first gambit. Time for a blitz." All the screens around the main monitor show multiple boxes with the word ONLINE.

Meanwhile, Eggman is extracting himself from his awkward position. After sidling out from between the grounded robots he is immediately on guard. He scans both ends of the street waiting for the next threat. It is eerily calm with no noise whatsoever rising from the city.

"Come now. Don't tell me that's all your tricks," he wonders silently to himself.

Finally the silence is broken by the sound of engines. Eggman gets into a ready position as what look like motorized unicycles charge at him from both ends of the street. All together there are about eight of them and they simultaneously start to circle the intruder as they get close. Their engines are loud and their agility is impressive but other than that the little mechanisms aren't very intimidating.

"Peh. Is that it?" Eggman kicks one and it falls into the unicycle ahead of it. They both fall and start writhing on the ground like upset turtles.

"Heh heh heh. Hey!" One of the unicycles attacks Eggman while his back is turned. It crashes through his legs and effectively trips him.

"Why you little-," he leaves the comment unfinished as the rest of the little robots swarm like vultures on a carcass. He recovers fast enough to jump away from them, but they follow him relentlessly. Eggman stands his ground, unwilling to run from such pathetic nuisances. With a sweeping kick he takes out five of them, but the last one manages to get around its fallen comrades. It then runs over Eggman's foot, eliciting a pained yelp from the intruder. Thoroughly annoyed now, he catches the small assailant by the top of the head and holds him up. With its only means of movement lacking a surface to move on, the unicycle can only spin its wheel helplessly and wait for the end. Eggman throws the bot into the air and with a flying spin attack, smashes it into a million pieces. Dusting off his gloves, Robotnik looks disgustingly satisfied in Sonic's opinion.

Just as before, a surprise attack comes at the exact moment the intruder thinks he is victorious. Eggman, however, has guessed this pattern and anticipates it. He runs out of the way as a heavy steel brick smashes the place where he had been standing. The brick is connected by a spaghetti arm to a floating eyeball which takes its other arm and repeats the motion. Eggman evades again and is about to launch a counterattack when two scythe wielding bugs come at him from the sides. Eggman ducks and the two end up decapitating each other. If that wasn't good enough, the two ton brick slams into them as well. Eggman, of course, isn't interested in joining the two robots in their smithereens state. He uses a spin attack to cut off the eyeball's arms, leaving the eyeball to roll away completely useless. A hammer nosed parrot decides it is his turn and dives at the intruder from a roof. Eggman is no longer underestimating an aerial attack. He steps out of the parrot's way letting it destroy itself against the ground. He then gives it a forceful stomp for emphasis.

Eggman cracks his knuckles idly wondering what the next robot will be. Nothing comes and he is surprised to see that he is once again alone. Before he can process this, a high pitched whistle causes him to turn. He sees…smudges. Eggman sputters as the black oil hits him in the face. Thanks to his glasses the retched stuff doesn't hurt his eyes, but it does blind him for a moment. The cheap trick annoys him more than it startles him and he mumbles to himself as he wipes the oil away from his eyes.

Eggman blinks a couple times to make sure what he sees is real.

Once able to see he finds himself in the center of an army of robots. They cover the street and the rooftops in their wide assortment of shapes and sizes.

And every single one is targeting the intruder in their midst.


	4. Give A Man A Lighter

Disclaimer: I do not own the Sonic characters.

Chapter 4: Give a Man a Lighter…

How they had done it, Eggman didn't know, but somehow an entire army of bots had been able to sneak up on him. Now both sides are waiting for the other to move, for a single slight motion to begin the conflict. Eggman eyes the forces around him, trying to decide where best to begin his attack. While turning his head to see more of the group, his foot skids to the right ever so lightly. It might as well have been a gunshot. The robots surge forward in an ungainly mob ready to decimate their target.

Unlike the guard robots outside the wall, there is a wealth of variety in this army inside the city. Unfortunately for Eggman, this variety includes a wide array of methods for destruction. As the attack begins, Eggman finds himself avoiding laser fire, axes, screwdrivers, nets, bludgeons, razors, stones, and a pitch fork. He jumps to evade everything except the laser fire which comes close enough to convince him that staying on firm ground is a safer bet. As he lands, Eggman takes out the bot that fired the shot which was shaped like a fish for some reason.

Now back on the ground, Eggman tucks into his ball form to do a spin dash. One apparently dim witted bot that looks like a winged mouse decides to attack the intruder in this state. It explodes immediately. Eggman rockets through the smoke of the dumb bot's remains and cuts through the legs of a horse with a slingshot. As it crumples, the intruder bounces up and above the gyrating torso of a humanoid robot. He smashes its head and deftly avoids the spinning mace hands. The height of this attack lets him take out one of the flying bots, something of a corkscrew helicopter with a swinging chainsaw connected to the bottom. Eggman goes threw the joint connecting bot and weapon, and causes the corkscrew to fall. A few of its brethren go with it when the chainsaw flails wildly and eventually gets imbedded in an unlucky snail bot. This chain of robot extermination would have continued but the next bot forces Eggman to halt. It is completely covered in spikes and not even a well powered spin dash could stop it from skewering him. Another hail of laser fire forces Eggman to think fast. He rests a booted foot underneath a spike and kicks up with all his strength. The bot upturns and Eggman spins into its unprotected underside. The bot explodes and Eggman continues his assault, but at a grudgingly slower pace.

That is the trouble with these types of forces. Unlike the monotonous design of the guards, these robots have unique defenses and attack styles. Using the same strategy for too long could be fatal if it isn't changed in time to cope with a bot that can counter it. Such a tactic doesn't stop an intruder like Eggman but it does throw off his momentum which is a battle won in itself.

In any case Eggman isn't letting something as trivial as overpowering numbers or a hostile force with unpredictable abilities deter him. He breaks the arms off a humanoid robot running at him with a lance, then grinds through the hull of a huge bot with a snake head, then… Eggman takes the luxury of a pause to peruse his next assailant. It is a small bot with a spherical shape set on a tricycle wheel. Two big eyes fill up most of its body and two short three pronged arms come out from its sides. To top it off is a flattened sombrero hat with a hook in the middle. Eggman's confusion lies in the sheer lack of intimidation in the little bot which for no apparent reason is waving at him enthusiastically.

Eggman's puzzlement is shared by Tails in the control room.

"Which model is that again," he asks.

"Um, well, actually," Sonic stutters, remembering what the bot is for, "I made that one to carry stuff around and, uh, I kind of sent it out there by mistake."

Tails gives Sonic a withering look.

"Hey. It's hard to keep track of them all and- ooh!"

On screen, Eggman recovers from his momentary pause and destroys the poor lackey bot. An accordion shaped robot tries to tie up his legs afterwards, but he kicks it off irritably and ducks as a horizontal pendulum arcs over his head. He then rushes to the body of the pendulum (nothing more than a pole with eyes) and grabs hold of it. In a blur of movement he catches the pendulum and causes it to rotate in a way similar to how children speed up merry-go-rounds. Once the movement is out of control, Eggman uses the pole to vault out of range. The resulting chaos causes a large swath of the army to be cut to pieces and the pendulum itself to break down. The whole process would have been very impressive except that when Eggman lands he does so in a puddle of oil. He falls in an ungainly heap and Sonic and Tails laugh hysterically for the second time that day.

Looking up with his nose covered in oil, Eggman sees a small bot with a hose and a container full of the irritating liquid. It is the same one that blinded him earlier. Now that it had caused him to slip as well, the robot looked understandably smug. Planning a very messy end for this particular robot, Eggman starts to get to his feet when a nine tailed lash strikes an inch from his face. He scrambles back and jumps to his feet but slips and falls again. This, strangely, is what saves as he feels the breeze off a hammer that just whizzed by his head. He tucks into a ball and dashes away destroying what bots he can but mostly just trying to get room to think. This delusion is quickly shattered as four blocky bots try to trap him between them. Eggman is forced to jump and is almost blasted by a laser again before he lands.

"He can't keep this up forever. The numbers are too great," Sonic says quietly and with less enthusiasm than might be attributed to such words. He knew from experience that right about now something usually went wrong. It is just as this thought crosses his mind that he sees it.

"Oh no."

There is a robot with a flame thrower approaching where the intruder landed. Add one bot that shoots fire and one bot that shoots oil and-

"Tails! We need to-"

But it is too late. Eggman has already spotted the bot and a wide evil grin blooms on his face. Throwing caution to the wind (not that he had much to begin with) he races up behind the flame throwing bot and earns a cut from an ax head in the bargain. It will be worth it if he can find the oil bot, however, and he quickly scans the robots closest to him. None of them are his target so he gets into a spin dash while still holding the flame bot. The result is an orb of flaming velocity that the intruder uses to good effect in clearing out an area around him. Somewhat singed and hoping any long range attackers were just incinerated, Eggman jumps as high as he can. At first, he sees nothing in the mesh of robots and wonders if the oil bot may have fled. Then he spots it between the legs of a bigger bot looking as if it wants to hide.

_Too bad,_ Eggman thinks with glee as he tosses the flame bot up and hits it in an overhead kick reminiscent of a pro soccer shot.

The aim is pinpoint accurate and the oil bot's eyes widen as it sees hot fiery death coming towards it. That's all it can do before the two unlucky forces collide.


	5. And Something Will Blow Up

Disclaimer: I do not own the Sonic characters.

Chapter 5: …And Something Will Blow Up

Eggman lands at the same time that the two bots hit each other and with his fastest acceleration yet, he runs outside the blast zone. The robots on the other hand aren't as lucky. Like a wave of red and yellow, the volatile reaction engulfs them. The damage is severe due to the fact that they are closely packed. It is a good formation when trying to overwhelm an intruder but not the best strategy when faced with an impromptu bomb. The initial explosion destroys the majority of the horde while the shrapnel takes out multiple others.

The remnants of the once impressive force are thrown into disarray which Eggman takes full advantage of. The area is still covered in smoke when he renews his attack, mercilessly ricocheting between enemies. In no time at all the entire army is gone.

Sonic notices with annoyance that Eggman is not injured, not even singed, by his ridiculously effective tactic. The hedgehog drops his head into the control panel (not gently) and sighs in frustration.

"Tails."

"Yeah."

"Next time I decide to send out all the robots, including two that can combust when in contact, can you knock some sense into me."

"Sure, but what do we do now?"

Sonic drags his eyes back to the screen. Robotnik is standing in the wreckage, happy as a cat in a fish market.

"Well," Sonic stands straight and stretches in a casual manner. All traces of irritation are gone, replaced by a look Tails doesn't like one bit. "I guess we'll just have to play the last card in our hand."

"What are you talking about?" As far as Tails knows the only robots they had that could combat the intruder are now scorch marks in the ground.

Sonic gives him a smile that is far too cheery.

"You'll see."

Eggman is running, enjoying the lack of an iron throat breathing down his neck. Now if he could just find that blue rodent, it would be a perfect day.

The city's structure is making the task difficult. It is built in a haphazard fashion with plants and factories placed in random spots and streets forced to curl around them. The result is a disorienting maze clearly designed to confuse intruders. Eggman is coming out of his fifth dead end when he sees a tower. It isn't overly tall but practically looms over the shorter, more business-like structures around it.

Eggman stops a second to think. If he were a mechanical genius and ruler of a city charged with technological might, he would choose the highest place he could to lord it over everyone else and let the shadows of his glory fill them with misery and woe. If he were said genius and had debilitating morals like that upstart hedgehog, he would still want the advantage of a high viewpoint.

Whatever the case, he bets that Sonic is in the tower and starts heading toward it. Well… he attempts to anyway. With so many twists and turns it's not as simple as it sounds, but he'll get there eventually!

Tails watches the monitor nervously as Robotnik makes his way progressively towards them.

"If you have a plan, I think you should try it now."

"Not just yet." Sonic walks over to the far wall and starts feeling around in the niche between two processing towers.

Tails arches a brow and is about to ask something when a loud crash brings his attention back to the screen.

Eggman, impatient with the windy route, is spin dashing through a wall (its purpose apparently just to be a wall). He comes out the other side and finds himself in an open area that Tails recognizes as the ground where robots could be tested en masse. From there it is a straight shot to the tower and, by association, to them.

"Sonic! You better hurry!"

"Hold on a minute," Sonic had his head squished into the niche so his voice is muffled, "Ah, there we go."

Whatever he did has some spectacular results as the entire control room shakes so violently that it knocks both of the occupants to the ground. It also loosens one of the monitors enough to make it fall and shatter on the floor.

From his position in the middle of the testing ground, Eggman can't feel the disturbance so much as hear a deep rumbling coming from somewhere. He turns in a complete circle trying to pinpoint the sound before some instinct causes him to look up. He does so just in time to save his life. Eggman runs out of the way as a square of steel hurtles into the ground where he had been. It leaves a small crater as a result and looking up Eggman can see why. The square of steel is part of a larger leg, one of four that connects to a massive cone shaped body. As he watches a ring of red illuminates the middle of it and the pointed tip of the cone breaks apart into four smaller legs.

In the control room, Sonic is helping Tails back to his feet while the fox looks at the new robot in puzzlement. It seems familiar to him for some reason but-

Realization crashes into him all at once.

"That's our roof!" He looks up half expecting the ceiling to be gone, but it's not.

"Yep. We are now five-hundred feet shorter."

"Why did you turn a roof into a robot?"

Sonic shrugs, "Gotta do something with my spare time."

Eggman isn't too worried. By now he is used to fighting enemies a hundred times his size (this wasn't the first time Sonic had used a giant robot and it certainly wouldn't be the last). He prepares to dart away as the metallic monstrosity raises a leg to crush him. He could have spared himself the effort as the robot moves as if it's swimming in molasses. Eggman moves out of the way as the steel foot finally lands. The robot tries the same thing with another leg and this time he stands still. He lets it come within an inch of his head before getting out of the way, then starts laughing.

As far as he could see the robot has no weapons and is slow to boot. Sure it's big, but that doesn't count much when it moves at a snails pace. The only trouble Eggman could see with it is that it is blocking the entrance to the tower which would force him to go back into the city to look for another route. Eggman idly wonders if Sonic is trying to irritate him to death as he goes back through the hole in the wall and back into the labyrinthine streets.

Tails looks at Sonic with worry clearly written on his face. Sonics meets the worried look with a confident one and calmly watches the monitor.

The robot whirrs softly, somehow figuring out that its target has left. Instead of trying to follow him the robot bends all its four longer legs so that it's in a crouching position. Then it jumps.

Eggman, meanwhile, has climbed to the top of a smoke stack in hopes that he can get a better view of the tower. This is made easier when a shadow passes over him, blocking the glare of the sun. He idly wonders where the cloud came from since it had been a featureless blue sky a minute ago. Eggman freezes, a suspicion worming its way into his mind. He slowly looks up. What he sees makes him jump off the smokestack and use a spin dash to grind down the sheer side as fast as he can. He wishes that gravity worked faster as the smokestack starts to break apart above him. When he hits the ground Eggman keeps the spin dash going and uses the speed of his fall to propel him away as the cone robot completely obliterates his former perch.

A giant robot jumping hundreds of feet in the air is impressive. Aforementioned robot landing on a target with perfect position from such a height is also impressive. The same robot landing on only one leg with the rest of it held in a precarious balance above it is downright unfair.

And dangerous as Eggman is finding out. All former slowness is gone from the robot. As soon as it lands, one of its airborne legs crashes down and barely misses the intruder's spinning form. Eggman comes out of his roll and dashes down a side street only to have it blocked by another steel foot. He turns back and has to skid underneath another leg to avoid being boxed in.

From then on he tries to stay in the wider roads but as he runs they become fewer and fewer. At one point he almost runs down a dead end but gets out before the robot can block the exit. It is at that moment that he figures out what the cone robot is trying to do. It blocks some roads, but lets him run down others. He realizes it is slowly steering him into an area where he can be caught and subsequently smooshed.

With this in mind Eggman jumps on a supply truck and uses it to get on a factory's roof. He isn't about to get penned in by some hunk of metal. It is time for an offensive.

The cone robot brings one leg level with the rooftop and slides it across to hit the intruder. Eggman waits until it is almost to him then jumps and lands on top. He then uses it as a bridge to get to the main body and spin dashes it. The result is disappointing. Eggman bounces off without even leaving a dent but he does hear an interesting sound.

He falls back to the ground with a plan already forming and runs deliberately down a dead end. He puts his back to the wall and waits for the cone robot to attack. It doesn't take long as it instantly strikes once Eggman is in a closed off area. The steel foot comes in at an angle and smashes the intruder into the wall.

Tails looks on in shock. "Is he-,"

"No," Sonic answers quickly, his confidence replaced by something unreadable.

A few moments pass in silence with the cone robot in the same position scanning for its target. There is a grinding sound and something round, fast, and annoying tunnels out of the wall. Eggman with nary a scratch to be seen rockets out of the hole and lands on the robots leg. Once again he starts using it as a bridge but this time the cone robot counter attacks by lifting another leg to try and brush him off. Eggman evades it with a spin dash that gets him out of range and flings him against the main body again. The reaction is the same but Eggman uses the rebound to land on the second leg. He runs across it and as soon as he gets to the joint he…vanishes.

Sonic smacks a hand to his forehead, apparently aware of exactly what would happen next.

A cacophony of thuds, clanks, and screeches echoes from inside the robot and it shudders as all four of its legs collapse. The cone somehow seems to crumple as the rounded sides fall inwards, giving it a contorted appearance. The four shorter legs seem to be the only parts undamaged until something bores a hole through them.

The short legs fall away to be replaced by Eggman standing on the defeated giant. Victorious.


	6. Last Line

This is the last chapter and with it I finish the first fanfiction I ever posted. Lots and lots of thanks to those that read and reviewed.

Disclaimer: I do not own the Sonic characters.

Chapter 6: Last Line

"That lucky little- How did he- It must have been a million-to-one chance." Sonic is pacing frantically while Tails looks nervous.

"Sonic he's-,"

"There was a slit in the joint. A narrow little sliver. I mean, how did he even fit!"

"Sonic, I think you should-,"

"Like a needle in a haystack. I knew he might realize it was hollow, but I never thought he'd-,"

"Sonic!"

Tails' yell breaks Sonic out of his tirade.

"He's coming this way."

On screen, Robotnik is running back to the place where the cone robot first appeared.

Sonic's brow furrows in thought and he starts pacing again, but this time at a less hectic pace.

"Will we have to leave the city?" Tails asks hesitantly.

"No," Sonic says by reflex. Abandoning the city was not an option. "If we do that we'll never get it back. We'll just have to think of something. That's what we do best after all."

"Yeah, but while we're here theorizing Robotnik could trap us. We should at least-,"

Sonic didn't listen after that. His mind had locked onto one particular word and it was giving him an idea that brought a wicked grin to his face.

"Tails you're a genius."

"Um, okay. Uh, why?"

Sonic puts an arm around the little fox's shoulders and gestures grandly.

"Because of you, I have a plan. A desperate plan, but one that I think will take care of our little intruder problem once and for all."

* * *

He had found it! Eggman couldn't remember ever being so happy to find an elevator in his life. At first he had gone to the building the cone robot had been guarding. It had taken a full top to bottom search before he came to the conclusion that there was no way into the tower. He had then gone back into the city and eventually found another hopefully adjoining building. Once again there was nothing. A _third_ building had finally gotten him to the elevator.

If this didn't work Eggman promised himself that he would burn the city to the ground and hope he got lucky.

He gets in and pushes the button for the top floor, suffering through annoying elevator music until the door pings. He waltzes into the room all ready to _finally_ confront his enemy only to find he's not there. Instead he finds himself in what looks like a storage room with boxes piled everywhere. Stranger still… there's no roof. He deflates visibly, his mustache drooping. Eggman had gotten misdirected for what must have been the hundredth time that day.

_I swear, that rodent gets some sick pleasure from all this_, Eggman thought.

He stomps back into the elevator and pushes the button for the second to top floor. The door opens and Eggman steps out warily, unsure whether to expect a death trap or a broom closet.

He's greeted by the sight of a long room with the wall space taken up almost entirely by monitors showing different views of the city. Except for the light from the screens the room is completely dark. Standing in the center of the room is the ruler of the most advanced city in the world and the obstacle in Eggman's path of destruction: Sonic the Hedgehog.

He looks bored.

"Took long enough. Did you get lost?"

"Listen hear you abominable little-," Robotnik stops himself short with an obvious effort. He takes a deep breath and is grinning once again.

"Actually I came to thank you."

Sonic narrows his eyes in suspicion.

"You see, compared to everything else on this planet you're the only one that puts up an actual challenge with your… interesting devices." He laughs, "Too bad they're so fragile."

Sonic has to strain himself not to snarl at that. It would be weeks before he could replace all his fragile devices.

"You've had your fun. Why not scamper off like a good little demon. There must be some cripple you need to trip or an orphanage you need to raze."

Robotnik pretends to consider this.

"That's true." He flexes his clawed gloves. "There's something I need to do before I leave."

He dashes forward before Sonic can react, but is stopped short by a pale blue barrier. He bounces back and lands with an audible thump.

"Ouch. Good thing you have that natural padding of yours or that could have hurt."

Robotnik leaps up, staring death at his nemesis through the shining blue screen.

"What. Is. This."

"Something you can't break through," Sonic says confidently.

"We'll see about that."

"I wouldn't do that if I were you." Sonic says as Eggman prepares to spin dash.

"Why ever not." Robotnik quirks a brow.

"Snippy, snippy. Go ahead and beat your head against it all day if you want. That's your choice. But I'd keep an eye over my shoulder if I were you. Who knows if something…unpleasant could come up that elevator."

Robotnik casts a glance behind him. There isn't much room between the barrier and the elevator doors. If reinforcements came, he would be hard pressed to escape. Even so he attacks the barrier, but gets repelled back harmlessly.

Sonic rolls his eyes and puts his arms behind his head like he has all the time in the world.

"Face it. It's a stalemate. Why not call it a day."

Robotnik ignores him, attacking again. His spin grinds against the barrier. For a minute, nothing happens. Then the barrie flickers and Robotnik slides through. Sonic is dumbfounded, eyes wide with shock.

"No! It's-,"

That's all he can say before he's slammed into one of the monitors by a blade backed glove. The screen breaks and Sonic can feel the shards digging into his back. He grits his teeth against the pain, willing to grant his enemy the satisfaction.

"One surprise after another. I must admit, defeating you has been an entertaining endeavor." Robotnik raises his other hand, ready to deliver the final blow. "But all good things come to an end. Any last words, hedgehog?"

"…Look…up." Sonic chokes out the words around the vice grip.

Robotnik chuckles and does so. Above his head is a rain of hissing acid. He gasps and jumps out of the way, dropping Sonic in the process. He's fast enough to avoid most of the deluge but as it splatters on the floor some of it lands on him. The concoction is strong enough to burn through clothing and Robotnik yelps as it starts eating into his shins.

"Sonic!" Tails flies down from the shadowed ceiling, where he'd been hiding with the bucket of acid.

"Perfect timing, bud." Sonic says from where he fell on the control panel.

"You alright?" Concern is evident in the fox's tone.

"I'll be fine. Let's hurry." He jumps off the panel, carefully avoiding the acid puddle. Robotnik is still rubbing his shins but recovers quickly. He tries to run at his foes but is met with a familiar blue wall.

"What?"

The barrier encompasses the entire room, even the floor and ceiling. Robotnik attacks it but nothing happens. He tries again with the same result.

Sonic and Tails are standing outside the barrier next to the only bare wall in the room. Tails is holding a remote control triumphantly.

"Did you really think you broke through the shield. I _let _you in. It was a trap so that you would-,"

"Ahem." Sonic is looking at Tails with a mixture of annoyance and amusement. Tails grins sheepishly and hands the remote to Sonic.

_Isn't it my job to do the taunting,_ Sonic thinks as he flicks a switch. The wall slides away to reveal a second elevator and the two step inside.

"Anyway, it seems like we've run out of time. Enjoy the next few seconds. They may be your last." Sonic waves mockingly and the doors close.

Eggman stood stock still. He didn't like the sound of that. He turns around and sure enough spots a tiny flame burning in the dark. It's connected to a rapidly disappearing string that ends at some sort of white powder. While Eggman didn't recognize the powder, he did understand the implications of the string. It's a fuse and that only meant one thing. A bomb!

* * *

The second elevator had been built exclusively for quick escapes. As such, it had more…acceleration. The elevator rockets to the ground with Sonic and Tails holding onto the support rails for dear life. Oddly enough there is annoying elevator music and when the ride finally comes to a jolting halt, the door opens with a playful ping. The unfortunate passengers are plastered to the ground for precious seconds before Sonic manages to get to his feet and helps Tails to his. They stumble out of the door and run to where Sonic had stationed some reserve guard bots. They duck behind them just as the control room blows.

The sound is like a thunderclap. It shakes the entire tower and all the surrounding structures. An inferno of golden flames devour the tower's top, followed by inky black smoke clouds that darken the sky for a few seconds. Giant chunks of masonry rain down from the wreckage but Sonic and Tails are far enough away to elude being squashed. Whatever debris that does reach them is blocked by the guard bots. After a moment the tower settles. The two breathe a sigh of relief.

"That was too close," Tails says.

"Indeed."

They both freeze and glance at each other. Neither of them had said that. They turn slowly and see a familiar spherical assailant standing on a wall. There is a glowing red jewel in his hand.

"Lucky I had this bauble. Chaos Control sure comes in handy."

"I hid that one." Sonic says, his voice dangerously quiet.

"In a cave? Behind three reinforced steel doors? With a lava moat and a piranha pit?" Robotnik tsks. "It was child's play."

"Fire." Sonic practically growls. The guard bots send out a hail of gun fire at their target but it does no good. Robotnik just dodges the rounds, all the while making faces at his now severely irritated adversary.

"I've reconsidered your offer." Robotnik says after the guards give up their useless task. "And I think I will call a stalemate on this one. Until next time."

He blows a raspberry and jumps backwards off the wall.

Sonic is clenching his fists like there is an annoying bald head in their grasp and Tails is wondering what to do when a little maintenance bot comes up. It tugs on Tails' glove to get his attention, then shows him a clipboard. As the fox reads it his face falls.

"Yes?" Sonic asks the question in a calm voice, but it doesn't quite mask his anger.

"Well…"

"Go ahead." Sonic takes a deep breathe and appears to be back to normal. He motions for Tails to speak.

"It's, um, a damage report. Seventy-five percent of the battle robots are gone. Four factories are out of commission. Numerous street damage, some underground problems and, well, since the control room went up in flames, our entire security system is down."

"Oh is that all? We better get to work then."

Tails blinks in surprise, but Sonic just takes the clipboard and walks off. He is almost out of sight when Tails hears Sonic yell at the top of his lungs-

**"I HATE THAT EGGMAN!"**

Fin


End file.
